Cathode ray tubes (CRTs) have been widely used in display devices to display image information on a screen. However, because CRTs are heavy and bulky, their use is being increasingly supplanted by slim, lightweight, low power-consuming liquid crystal display devices (LCDs) providing high brightness and large screens at low prices. Compared to other display devices, including CRTs, LCDs provide high resolution and rapid response times when displaying moving images.
An LCD relies on optical anisotropy and polarizability of liquid crystal molecules to produce an image. Liquid crystal molecules are aligned with directional characteristics resulting from their long, thin shapes. These directional characteristic can be artificially controlled by applying an electric field to the liquid crystal molecules. By changing the arrangement of the liquid crystal molecules as light is transmitted therethrough, an appropriate image can be displayed.
Twisted nematic (TN) mode LCDs are among the most widely used LCDs. In a TN mode LCD, electrodes are installed on each of two substrates and a director of liquid crystals is twisted at 90°. When a voltage is applied, the director of liquid crystals is driven. A principal disadvantage of TN mode LCDs is that they often provide narrow viewing angles.
To address the narrow viewing angle problem, in-plane switching mode LCDs (IPS-LCDs) and fringe field switching mode LCDs (FFS-LCDs) have been developed. An FFS-LCD can provide a wide viewing angle and improved transmittance compared to an IPS-LCD. In an FFS-LCD, common electrodes and pixel electrodes are formed from a transparent conductive material. A narrower gap is formed between the common electrodes and pixel electrodes than in the top and bottom substrates. Therefore, a fringe field is formed between the common electrodes and the pixel electrodes, driving the liquid crystal molecules at upper portions of the electrodes.
FIG. 1 is a plan view of a related art FFS-LCD depicting a gate line 102 intersecting a data line 104 to define a unit pixel. A thin film transistor (TFT) is formed at a crossing between the gate line 102 and the data line 104. A common electrode 105 is formed from a transparent conductive material and is disposed on an entire surface of the bottom substrate. The common electrode 105 is electrically connected to a common line 107 and can continuously receive common signals therefrom. The pixel electrode 108 is also formed of a transparent material and is overlapped by the common electrode 105 and an insulation layer (not shown). The insulation layer is interposed between the pixel electrode 108 and the common electrode 105. The pixel electrode 108 includes a plurality of slits 108a spaced from one another at a predetermined distance. The common electrode 105 is exposed by the slits 108a. 
Although not shown, the top substrate facing the bottom substrate has a broader gap therebetween compared to the gap between the pixel electrode 108 and the common electrode 105. A liquid crystal layer is interposed between the top and bottom substrates. The electrode structure pattern formed from the transparent conductive material in the pixel electrode 108 of an FFS-LCD is designed to reduce color shift.
FIG. 2 is a plan view of another related art FFS-LCD, identifying common or similar features according to the reference numbers identified in FIG. 1. In FIG. 2, a plurality of slits 108a is arranged in a comb pattern on the pixel electrode 108 forming two domains of equidistant-spaced slits 108a. 
FIG. 3 is an enlarged view illustrating an end portion A in the pixel electrode 108 of FIG. 2. FIG. 4 is a picture illustrating brightness of the end portion A in the pixel electrode 108 of FIG. 2.
As illustrated in FIGS. 3 and 4, when power is applied to the common electrode 105 and the pixel electrode 108, a multi-directional electric field is generated at the end portion A of the pixel electrode 108. The multi-directional electric field produces a reverse twist region, characterized by multiple rotational directionalities among the liquid crystal molecules. This generates a disclination line. As a result of the disclination line, there is reduced brightness in an end portion of the pixel electrode, as well as reduced contrast ratio. Accordingly, the disclination line results in a reduced aperture ratio in the pixel area and reduced image quality.